This paper evaluates whether direct democracy supplements or undermines traditional representative democracy. While a first approach assumes that a culture of active direct democracy stimulates citizens political interest and ultimately bolsters participation in parliamentary elections, a competing hypothesis proposes a negative relationship between the frequency of ballot measures and electoral participation due to voter fatigue and decreased significance of elections. Our multilevel analysis of the 26 Swiss cantons challenges recent studies conducted for the U.S. states: In the Swiss context, where direct democracy is more important in the political process than the less salient parliamentary elections, greater use of direct democratic procedures is associated with a lower individual probability to participate in elections. Furthermore, by distinguishing between short and long-term effects of direct democracy, we show that the relationship observed is of a long-term nature and can therefore be seen as a result of adaptive learning processes rather than of instantaneous voter fatigue.